Power bank



FIG. 1 shows the perspective view of the front and left side of a power bank showing my new design,

FIG. 2 is the perspective view of the rear and right side thereof,

FIG. 3 is the front view thereof,

FIG. 4 is the rear side view thereof.

FIG. 5 is the right side view thereof,

FIG. 6 is the left side view thereof,

FIG. 7 is s the top view thereof; and,

FIG. 8 is the bottom view.

The broken lines in the drawings depict portions of the power bank that form no part of the claimed design. 

CLAIM I claim the ornamental design for a power bank, as shown and described. 